Offshore Plug and Abandonment Operations with Coiled Tubing Service from Light Workover Vessel: A Case Study from Brazil Deepwater

Abstract

Abstract The demand for well plug and abandonment (P&A) operations in Brazil has increased significantly during the last 3 years, resulting in a steep learning curve that can lead to development of state-of-the-art methodologies that save time, reduce operational risks, and provide reliable cost-effective solutions. This paper presents a comprehensive analysis of recent well abandonment operations in a mature field in Brazil, which included wells that were depleted or no longer economically viable. A methodology is discussed and highlights the use of a casing collar locator (CCL) to perform depth correlation before setting packers and placing cement plugs, real-time pressure signals to monitor packer setting, and coiled tubing (CT) internal and external pressure management to help ensure that all cement is pumped out of the CT.